Raman spectra of trifluoromethylsulfinyl fluoride, trifluoromethylsulfinyl

Hans-Georg Mack and Heinz Oberhammer, J rgen Jacobs, Marc Kronberg, and Helge Willner. Inorganic Chemistry 1996 35 (4), 806-810. Abstract | Full Text ...
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CF3S(O)F, CF3S(O)Cl, and FS(0)Cl shown in eq 5 requires very little opening of the unbroken A1-C-A1 bond angle to facilitate rotation. However, in 4, the bond angle must be opened further to allow attack by a TMA monomer. This is consistent with the slightly higher activation energy and the more negative entropy of activation found for the exchange between 1 and 3 and compared to the exchange in TPTA. Registry No. TPTA dimer, 17439-80-4; T M T A dimer, 56030-41-2; T M A dimer, 15632-54-9; tetramethyldi-p-tolylaluminum, 17439-75-7; pentamethyl-p-tolylaluminum, 17439-77-9.

References and Notes (1) Presented in part at the 6th Central Regional Meeting of the American Chemical Society, Detroit, Mich., 1974, and the 169th National Meeting of the American Chemical Society, Philadelphia, Pa., 1975. (2) K. C. Williams and T. L. Brown, J . Am. Chem. Soc., 88, 5460 (1966). (3) T. L. Brown and L. L. Murrell, J . Am. Chem. Sot., 94, 378 (1972). (4) E. A. Jeffery and T. Mole, Aust. J . Chem., 22, 1129 (1969). (5) E. A. Jeffery and T. Mole, Aust. J . Chem., 26, 739 (1973). (6) N. Muller and D. E. Pritchard, J . Am. Chem. Soc., 82, 248 (1960). (7) K. C. Ramey, J. F. O’Brien, I . Hosegawa, and A. E. Borchert, J . Phys. Chem., 69, 3418 (1965). (8) A . W. Laubengayer and W. F. Gilliam, J . Am. Chem. SOC.,63, 477

(1941). (9) M. B. Smith, J . Organomet. Chem., 46, 211 (1972).

Inorganic Chemistry, Vol. 14, No. 10, 1975 2431 (10) M. B. Smith, J . Organomet. Chem., 46, 31 (1972). ( 1 I ) 0. Yamamoto, K. Hayamizu, and M. Yanagisawa, J . Organomet. Chem., 73, 17 (1974). (12) G . Zweifel and G.M. Clark, J . Organomet. Chem., 39, C33 (1972). (13) E. A . Jeffery, T. Mole, and J. K. Saunders, Aust. J . Chem., 21, 137 ( 1968). (14) H. D. Visser and J. P. Oliver, J . Am. Chem. Soc.. 90, 35, 79 (1968). (15) J. F. Malone and W. S. McDonald, J . Chem. Soc., Dalton Trans., 2646 (1972). (16) J. F. Malone and W. S. McDonald, J . Chem. Sot. A, 3362 (1970). (17) J. F. Malone and W. S. McDonald, J . Chem. Soc., Dalton Trans., 2649 ( 1972). (18) D. A. Sanders and J. P. Oliver, J . Am. Chem. Sor., 90, 5910 (1968). (19) D. F. Shriver, “The Manipulation of Air-Sensitive Compounds”, McGraw-Hill, New York, N.Y., 1969. (20) H. Gilman and R. E. Brown, J . Am. Chem. Soc., 52, 3314 (1930). (21) F. C. Whitmore and R. J. Sobatzki, J . Am. Chem. Soc., 55, 1128 (1933). (22) E. Krause and P. Dittmar, Chem. Ber., 63, 2401 (1930). (23) J. J. Eisch and W. C. Kaska, J . Am. Chem. Soc., 88, 2976 (1966). (24) J. Surtees, Rev. Pure App/. Chem., 13, 91 (1963). (25) A. L. VanGeet, Anal. Chem., 40, 2227 (1968). (26) J. A. Pople, W. G. Schnieder, and H. J. Bernstein, “High Resolution Nuclear Magnetic Resonance”, McGraw-Hill, Kew York, N.Y., 1959, Chapter I O , and references therein. (27) K. L. Henold, J. Soulati, and J. P. Oliver, J . Am. Chem. Soc., 91, 3171 (1969). (28) A. A. Frost and R. G. Pearson, “Kinetics and Mechanism”, Wiley, New York, N.Y., 1961.

Contribution from the Department of Chemistry, University of Idaho, Moscow, Idahe 83843

Raman Spectra of Trifluoromethylsulfinyl Fluoride, Trifluoromethylsulfinyl Chloride, and Sulfinyl Chloride Fluoride R O B E R T L. K I R C H M E I E R and JEAN’NE M . S H R E E V E *

Received January 22, 1975

AlC5005 1Z

Gas-phase infrared (2000-400 cm-I) and liquid-phase Raman spectra (2000-100 cm-1) for C F S ( O ) F , CF3S(O)CI, and FS(0)CI are reported, and vibrational analyses are made for the three molecules. Depolarization ratio measurements indicate that the compounds belong to symmetry species CI and thus are pyramidal in agreement with lone-pair repulsion considerations.

Introduction A relatively large number of sulfinyl halides have been synthesized and characterized by vibrational spectral analyses.1-7 We report here the infrared and Raman spectra and vibrational assignments for the unsymmetrical sulfinyl halides CF3S(O)F, CF3S(O)Cl, and FS(0)Cl. Although the assignments for FS(0)Cl are tentative due to the impurity of the sample, comparative analyses of the spectra for all three compounds gave rise to consistent results. The structures of the three compounds have not been determined; however, a pyramidal geometry is predicted from lone-pair repulsions. The three molecules may belong to point group CS(planar) or to point group CI(pyramidal). Related sulfinyl compounds S(O)F2,8 (CF3)2S0,9 and S(O)C1210 have been shown to be pyramidal. Experimental Section Bis(trifluoromethy1)disulfane (PCR, Inc.) was allowed to react with AgF2 a t 0’ for 12 hr to give good yields of CF3SF3.11 The CF3SF3 was then carefully hydrolyzed to give quantitative yields of C F S ( 0 ) F . Pure C F S ( 0 ) F was obtained by gas chromatography using a column constructed of 0.25-in. 0.d. copper tubing packed with 25% FS 1265 on Chromosorb P. When HCI was allowed to react with CF3S(O)F for 1 hr a t 25O, good yields of CFS(O)CI12 were obtained. It was also purified by gas chromatography using the same column. F S ( 0 ) C I was obtained from the reaction between equimolar quantities of CIF (Ozark-Mahoning) and SOClz at -78O over a period of 12 hr. Yields of F S ( 0 ) C I approached 50%. T h e F S ( 0 ) C I was purified somewhat by low-temperature distillation.

Infrared spectra were recorded on a Perkin-Elmer Model 621 grating spectrometer. Gas-phase infrared spectra were obtained by using a 7-cm glass cell equipped with KBr windows (pressures from 5 to 35 Torr). A Jarrell-Ash Model 25-300 Raman spectrometer equipped with a Coherent Radiation Model C R - M G krypton-argon laser (4880 A for CF3S(O)F and C F S ( O ) C I and 5308 8, for FS( 0 ) C l ) was used to record the Raman spectra. Samples for liquid-phase Raman spectra were sealed in 0.4-cm 0.d. Pyrex tubes. Rotation of a half-wave plate by 45’ turned the direction of the electric vector of the incident light through 90°, allowing the measurement of depolarization ratios.

Discussion and Results For both CF3S(O)F and CF3S(O)Cl, 14 of the expected 15 fundamentals are observed in the Raman spectrum, while all six fundamentals are observed in the case of FS(0)Cl. For CIsymmetry, all bands in the Raman spectrum are expected to be polarized, and this is observed. All bands are both infrared and Raman active. In Figure 1 are the Raman spectra of CFjS(O)F and CF3S(O)C1. The Raman and infrared spectral data and the assignments for CF3S(O)F and CF3S(O)CI are given in Table I. The Raman and infrared spectra and band assignments for FS(0)Cl are found in Table 11. The small number of bands observed in the infrared spectrum is a result of complete absorption by the KBr windows below 400 cm-1. Although mixing of some of the fundamentals may occur, group theory provided a basis for at least first approximations of band assignments. It was most convenient in this study to

2432 Inorganic Chemistry, Vol. 14, No, 10, 1975

Robert L. Kirchmeier and Jean'ne M. Shrezvc

Table 1. Raman and Infrared Spectra for CF,S(O)F and CF,S(0)Cla CF,S(O)Cl CF,S(O)F

__l__ll

____________

.

Infrared (gas), cm-'

Raman (liquid), cm-'

Infrared (gas), cm -'

1267vs

1257 m

1242s

Raman (liquid), cm-'

Assignment _ I _ _ -

I _ _ _

S=O str

1205-1260

w,SI1 1226vs 1213vs 1152vs 749 S, br 590m 555vw 480m 409m

1227w 1217w 1142w 757 vs 745-710 m, ski 587w 55ow

1218s 1123s 1096mw 751 m 577 w 551 w 489 m 461w

480m 413s 342 m 289 vs

5tI

C Y , str

CF, str CF, def S --F str

574 w 553 w 489 s 463 m 346 vs

CF, def CF, def S--Cl str C--.S str S=O wag S-F wag CF, rock S-Cl wag CF, ;ock c-s wag CF, torsion

301 s 267 m 211 w 163 in Not obsd

220 m 192 w Not obsd a

CF,

1190 in 1120 w 1 1 0 0 ~ 752 s

Key: sh, shoulder: w, weak; m, medium; s, strong: vs, very

strong.

Wguare 1. Raman spectia o f CF3S(0)F (A) and CT,S(O)Cl (B) (cm-' 1.

The SF stretching frequency in I;

Table II. Raman and Infrared Spectra for F'S((3)Cl

Infrared, cn-'

Raman, cm-' _

1293 vs 1 5 1 vs 514 s 435 w

_

_

~

_

l

-

1216 m 739 m 493 s 444 vs 341 s 314 vs

-

Assignment -

l

_

l

l

_

l

_

_

_

l

l

_

S=O str S-F str S--C1 str S=Q wag S--F wag s--c1wag

consider the spectra in terms of the bands due e o CF3X (X = S ( 0 ) F or S(0)Cl) and the bands due to X§(O)F or XS(0)Cl (X = CF3 or F). In this way a common basis for detailed vibrational analysis was obtained. That is, the six fundamental vibrations of FS(Q)Cl may be described roughly as three stretching modes, SO, SF, and SC1; two wagging modes, SF and SCI; and the FS(O)Cl deformation mode (or SO wagging mode). Analogously, the 15 fundamentals for CF3S(O)F ( C F S ( 0 ) C l ) can be pictured as 9 CF3X modes (3 stretchings, 3 deformations, 2 rockings, and 1 torsional) and 6 XS(0)F (X = CF3) modes (SO, SF, and SC stretching; SF, SC, and SO wagging). Sulfur(1V)-oxygen stretching frequencies assigned previously in the literature include S(O)F2 (1333 cm-l),' (CF3)2SO (1242 cm-l),9 S(O)C12 (1229 cm--1),3 and S(O)Br2 (1121 cm-l).4 W e have assigned the SO stretching frequency in CF3S(Q)F, CF3S(O)C1, and FS(O)Cl to bands at 1267, 1242, and 1276 cm-1, respectively. It appears that the SO stretching frequency is related approximately to the electron-withdrawing ability of the atoms or groups attached to the sulfur, and this trend is reflected in the assignments we have made; e.g., the sulfur-oxygen stretching mode occurs a t the highest frequency in S(O)F2, and the trend is S(O)F2 ? FS(0)Cl ? CF3S(o)]F > (CF3)2SQ C F S ( 0 ) C l > S(O)C12 > S(O)Br2. A similar order, due primarily to an increasing mass effect, is observed for bands assigned to the sulfur-oxygen wagging motion: S(O)F2 (526 cm-.l),l (CF3)2SO (373 cm-l),B S(O)C12 (344 cm-I),3 S(O)Br2 (267 cm-1),4 and, including the compounds studied here, S(O)F2 > FS(0)Cl (444 cm-1) > CF3S(O)F (413 cm-1) > (CF3)2SO > CF3S(Q)Cl (346 cin-I) S(O)C12 > S(O)Br2. The sulfur-oxygen wagging mode in S(O)F2 had been assigned to a band in the spectrum at 326 cm-1;3 however, force constant calculations7~13have supported the assignment of the band a t 526 cm-1.

-

-

i s assigned readily metrical stretching e two SF4 antisymmetric 728 cm--li respcctively. However, for CF3S(O)F the SF stretching mode is not immediately apparent. 'The broad band in &heinfrared spectrum centered a t 749 cm-1 might be assigned to one of' the CF3 deformation modes, but it ' h more intense than) a similar (751 c n - 1 in the infrared band observed in CF3S spectrum). CF3 deforma des around 750 cm-1 appear to be sharp and strong in the Raman spectra.9 'The expanded Rainan spectrum of C F S ( 8 ) F between 700 and 800 crn - 1 shows clearly two bands in the 750-cr0-1 region. The strong, sharp band a t 757 em-1 is assigned to one of the CF3 deformation modes and a shoulder of medium intensity from 745 to 710 c n r l is assigned to the SF stretch. The latter band is not present in the spectrum of CF'3S(O)CI. An alternate, and perhaps niore rcalistlc, explanation is that mixing of symmetry coordinates occurs for fundamentals such as these having the same symmetries with frequencies in dose proximity. The intense Raman band a t 757 cm-1 would result from a symmetric combination and the medium band at 745-7 10 cm-1 From an antisymmetric combination of the symmetry coordinates. Among the S-C1 stretching frequencies which have been reported in the literature are SO2C12 (syrnmetrica.1406 cm-l),ls S(0)Clz (symmetrical 490 cm-1),3 SCh (525 cm--1),16S2C12 (460 cm--l),16,and CF3SSCI (490 cm-').I7 two possibilities for the SC1 stretch in C F S ( at 346 and 489 em-I. Both are strong bands in the Raman spectrum; however, we assigned the band a t 346 cm-1 to the SO wagging mode, since it fits the trend for other reported SO wagging motions more closely than does the band a t 489 cm--l, Thus the latter must be assigned to the S-Cl stretching frequency. Similar reasoning was used to differentiate between the two possibilities in FS(0)Cl. The band a t 493 cm-1 was assigned t~ the SC1 stretching frequency and the band a t 444 cm-1 bo the SO wagging mode. The SF wagging naode was assigned to the band at 342 cm--l for CF3S(Q)F and to 347 cm-1 for FS(0)Cl. Previously, S-.IF wagging fundamentals for SF618 and S02FBr3 had been assigned to bands at 344 and 320 cm--l, respectively. SS(0)Cl. exhibits an S@lwagging mode ah 314 cn1-1~while in CF3S(0)CI the analogous mode was assigned to a band at 26'1

Inorganic Chemistry, Vol. 14, No. 10, 1975 2433

Alkoxychlorocyclotriphosphazenes cm-1. The value for the SCl wagging motion in SFsCl is reported to be 270 cm-1.19 Recently several CF3S-containing molecules have been studied, and the C-S stretching frequency was reported to be 475 cm-1 for CF3SCF3,9 468 cm-1 for CF3S(O)CF3,9 and 446 cm-l for CF3SSCF3.9JO Thus, we have assigned the C-S stretch in C F S ( 0 ) F and CF3S(O)C1 to the bands of medium intensity at 480 and 463 cm-1, respectively. As mentioned previously, there should be nine bands associated with the CF3X portion of the CF3S(O)Cl and CF3S(O)F molecules. Three of these should be stretching bands. These three vibrations should lie in the range 1100-1400 cm-1.21-23 There are four bands in this region in the infrared and Raman spectra of each of these compounds. One of these (the highest frequency band in each case) has been assigned to the SO stretching frequency. The others, very strong in the infrared spectra and weak in the Raman spectra, may be assigned to the three CF3 stretching fundamentals. Although the values of the CF3 stretching frequencies for CF3S(O)F and CF3S(O)Cl are quite different, the shift of the frequencies of the latter to lower energy causes the positions of the absorbance bands in this region of the spectrum to be nearly identical with that of (CF3)2S09 which is reasonable. The three expected CF, deformation modes are observed and are easily assigned by comparison to assignments made for CF3S(O)CF3 (753, 591, and 558 cm-l)9 and CF3SSCF3 (760, 573, and 545 cm-l).9 Thus, we have assigned the three bands at 757 (see discussion of S-F stretching mode), 587, and 550 cm-1 to the CF3 deformation modFs of CF3S(O)F and those at 752, 574, and 553 cm-1 to analogous vibrations in CFB(0)Cl. By similar comparisons, the CF3 rocking modes were assigned to the bands at 289 and 220 cm-1 for CF3S(O)F and 301 and 21 1 cm-1 for CF3S(O)C1. CF3 rocking modes had been assigned previously as high as 49021 and as low as 14924 cm-1. According to Haas and coworkers,25-27 an intense band around 300 cm-1 (289 and 301 cm-1) is characteristic of CF3 rocking motions. Finally, the CF3 torsional mode is not observed in either case and probably falls below 100 cm-l in the Raman effect.28329 It has been observed at 75 cm-1 in the case of CF3SCF3 and CF3S(O)CF3.9

Acknowledgment. Fluorine chemistry research at the University of Idaho is supported by the Office of Naval Research and the Nationzl Science Foundation. We are indebted to Dr. Thomas Loehr of the Oregon Graduate Center for obtaining the Raman spectra. We thank one of the referees for helpful suggestions concerning the assignment of bands in the 750-cm-1 region of the CF3S(O)F spectrum. Registry No. CF3S(O)F, 812-12-4; CF3S(O)CI, 20621-29-8; FS(O)CI, 14177-25-4; CF3SF3, 374-10-7; CIF, 7790-89-8; SOC12, 7719-09-7.

References and Notes J. K. OLoane and M. K. Wilson, J . Chem. Phys., 23, 1313 (1955). A. J. Downs, D. A. Long, and L. A. K. Staveley, Ed., “Essays in Structural Chemistry”, Plenum Press, New York. N.Y., 1971, pp 466-467. R. J. Gillespie and E. A. Robinson, Can. J . Chem., 39, 2172 (1961). H. Stammreich, R. Forneris, and Y . Tavares, J . Chem. Phys., 25, 1277 (1956). R. A. Suthers and T. Henshall, 2.Anorg. Allg. Chem., 388, 269 (1972). N. J. D. Lucas and J. G. Smith, J . Mol. Spectrosc., 43, 327 (1972). E. L. Pace and H. V . Samuelson, J . Chem. Phys., 44, 3682 (1966). P. Bender and J. M. Wood, J . Chem. Phys., 23, 1313 (1955). H. A. Carter, C. S. Wang, and J. M. Shreeve, Spectrochim. Acta, Part A , 29, 1479 (1973). C. A. McDowell, Trans. Faraday Soc., 49, 371 (1953). E. W. Lawless and L. D. Harman, Inorg. Chem., 7, 391 (1968). C. T. Ratcliffe and J. M . Shreeve, J . Am. Chem. Soc., 90,5403 (1968). D. A . Long and R. T. Bailey, Trans. Faraday Soc., 59, 792 (1963). R. A. Frey, R. L. Redington, and A. L. K. Al.jibury, . . J . Chem. Phys., 54, 344 (i97i). D. E. Martz and R. T. Lagemann, J . Chem. Phys., 22, 1193 (1954). 1. R. Beattie and H. Chudzvnska. J . Chem. Soc. A , 984 (1966). N. R. Zack and J. M. Shrew;, Inorg. Nucl. Chem. Lett., 10,’619(1974). R. T. Lagemann and E. A. Jones, J . Chem. Phys., 19, 543 (1951). L. H. Cross, H. L. Roberts, P. L. Goggin, and L. A. Woodward, Trans. Faraday Soc., 56, 945 (1960). S. N. Nabi and N. Sheppard, J . Chem. Soc., 3439 (1959). J. R. Durig and D. W. Wertz, J . Mol. Spectrosc., 25, 456 (1968). R. P. Hirschrnann, W. B. Fox, and L. R. Anderson, Spectrochim. Acta, Part A , 25, 81 I (1969). F. A. Miller and F. E. Kiviat, Specirochim. Acta, Part A , 25, 1577 (1969). E. L. Pace, A. C. Plaush, and H. V. Samuelson, Spectrochim. Acta, 22, 993 (1966). A. J. Downs and A. Haas, Spectrochim. Acta, Pari A , 23, 1023 (1967). A . Haas, Chem. Ber., 97, 2189 (1964). A. Haas and P. Schott, Chem. Ber., 101, 3407 (1968). C. V. Berney, Spectrochim. Acta, 21, 1809 (1965). K. R. Loos and R. C. Lord, Spectrochim. Acta, Part A , 27, 777 (1971).

Contribution from the Department of Chemistry, The Pennsylvania State University, University Park, Pennsylvania 16802

Reaction of Sodium 2,2,2-Trifluoroethoxidewith HexachlorocyclotriphosphazenelJ J. L. S C H M U T Z and H. R. ALLCOCK” Received March 10, 1975 AIC50179G The reaction between sodium 2,2,2-trifluoroethoxide and hexachlorwyclotriphosphazene (I) yielded nine cyclotriphosphazenes of the formula N ~ P ~ ( O C H ~ C F ~ where ) ~ C ~n -=R1-6. Nuclear magnetic resonance analysis indicated that these products were compounds 11-X. This constitutes the first isolation and identification of a complete series of alkoxychlorocyclophosphazenes. The reaction was found to follow almost exclusively a trans-nongeminal pathway, and a steric rather than an electronic “cis effect” is postulated to account for this pattern. Dipole moments were measured, but these were shown to be unsuitable for isomer identification, presumably because of the presence of the bulky, nonrigid trifluoroethoxy groups and a nonvanishing ring moment. The applicability of these results to related high molecular weight polyphosphazene systems is discussed.

Introduction The syntheses of several fluoroalkoxycyclophosphazenes, including hexakis(2,2,2-trifluoroethoxy)cyclotriphosphazene (X), were first reported in 1959 and 1962.334 Later, the synthesis of tris-, tetrakis-, and pentakis(trifluoroeth0xy)chlorophosphazene trimers was reported,s and the N M R spectrum of trifluoroethoxypentachlorocyclotriphosphazene (11) was described.6 Apparently no attempts were made to

identify the geometric isomers formed when alternative structures were possible. The current interest in high molecular weight polyorganophosphazenes7-15 has generated a need for new information about the replacement patterns that exist when alkoxy substituent groups replace chlorine atoms in phosphazene systems. The present study was undertaken in an effort to synthesize, separate, and identify the stereoisomers